Impact of the MEDEA exposure-reduction strategies on indoor air quality during desert dust storms

Abstract Background Desert dust storms (DDS) impact the Mediterranean basin heavily, particularly in the context of climate change, reduced precipitation and increasing desertification. There is a pressing need to develop policies protecting EU citizens’ health from DDS. While Public Health authorities in affected regions commonly issue warnings, the effectiveness of recommendations to reduce exposure has not been documented. Methods This work is part of the wider “MEDEA” intervention studies, co-funded by LIFE 2016 Programme. Among other outcomes, the studies examined the effectiveness of an indoor exposure-reduction intervention (i.e., decrease home ventilation and use of air cleaners) across homes of asthmatic schoolchildren and individuals with atrial fibrillation in Cyprus. Participants were randomized to either a control or indoor intervention group. The assessment took place in a sample of participants’ homes, during 2019 and 2021, with the collection of indoor and outdoor PM10 and PM2.5 samples, which were analyzed for mass and elemental concentrations. Results Indoor PM2.5 and PM10 mass and elements concentrations were significantly lower in the indoor intervention group compared to the control group, both during days with no dust (e.g., 55% and 48% reduction for PM2.5 and PM10, respectively) and days with desert dust (PM2.5: 47% and PM10: 40% reduction). In addition, the infiltration of PM2.5 and PM10 particles from the outdoor to the indoor air was significantly lower in the intervention vs. the control group (PM2.5: -55%, 95% CI: -42%, -65%; PM10: -41%, 95% CI: -61%, -12%). Conclusions The study assessed a realistic exposure-reduction strategy and provided first-time evidence that closing doors and windows along with air cleaners can reduce indoor exposure to DDS particles. This evidence can further inform decision-making and strategic planning for population-level mitigation of DDS health effects in Mediterranean Europe. Key messages Decreasing home ventilation and use of air cleaners during DDS can reduce indoor particle mass concentrations by up to 50%, and infiltration of particles from outdoor environments by up to 60%. Demonstration of the effectiveness of a sustainable exposure-reduction intervention can contribute towards the adaptation of the population to the effects of climate change.


Background:
The world population is ageing, and their health needs imply substantial demands on health systems. Remote Patient Monitoring (RPM) may help elderly patients live independently in their homes for longer. The essence of RPM is the continuity of use, which is challenging for wearable devices and patient-led technologies. Unobtrusive (ambient) sensors could be an innovative solution, such as motion detectors and similar technologies. This study aims to review the evidence on the effect of ambient sensors on healthcare use by the elderly. Methods: This is a systematic review for narrative synthesis, searching five databases, Medline, Embase, CINHAL, Scopus and Web of Science, on 21 Feb 2022 without setting a lower time limit. No restrictions on the design of studies were applied. A metaanalysis was not feasible due to the heterogenicity of the studies.

Results:
Out of 5,653 search results, 180 studies were subjected to fulltext review, of which 6 studies were included in the final synthesis. All the included studies were conducted in the USA. Four studies assessed the technology's cost-efficiency, while only one reported significant cost savings. One study reported a significant reduction in hospital days and visits to a physician among the users. Using ambient sensors was associated with an increased length of stay in facilities where the elderly can live independently, including at home. The impact on the number of hospitalisations or emergency room visits was unclear.

Conclusions:
Our review identified limited evidence on the effect of ambient sensors on healthcare use by the elderly. The potential has been demonstrated for ambient sensor technologies to result in cost savings; however, further research is needed to assess the impact on health outcomes. Key messages: Ambient sensors can be effectively used to remotely monitor the health of eldelry people at home. Further research is needed to assess the cost effectiveness of using ambient sensor technologies in remote patient monitoring.
precipitation and increasing desertification. There is a pressing need to develop policies protecting EU citizens' health from DDS. While Public Health authorities in affected regions commonly issue warnings, the effectiveness of recommendations to reduce exposure has not been documented.

Methods:
This work is part of the wider ''MEDEA'' intervention studies, co-funded by LIFE 2016 Programme. Among other outcomes, the studies examined the effectiveness of an indoor exposurereduction intervention (i.e., decrease home ventilation and use of air cleaners) across homes of asthmatic schoolchildren and individuals with atrial fibrillation in Cyprus. Participants were randomized to either a control or indoor intervention group. The assessment took place in a sample of participants' homes, during 2019 and 2021, with the collection of indoor and outdoor PM10 and PM2.5 samples, which were analyzed for mass and elemental concentrations.

Conclusions:
The study assessed a realistic exposure-reduction strategy and provided first-time evidence that closing doors and windows along with air cleaners can reduce indoor exposure to DDS particles. This evidence can further inform decision-making and strategic planning for population-level mitigation of DDS health effects in Mediterranean Europe.

Key messages:
Decreasing home ventilation and use of air cleaners during DDS can reduce indoor particle mass concentrations by up to 50%, and infiltration of particles from outdoor environments by up to 60%. Demonstration of the effectiveness of a sustainable exposure-reduction intervention can contribute towards the adaptation of the population to the effects of climate change.
Exposure to air pollution is a known risk factor for asthma exacerbations, emergency attendances and hospitalisations. In Europe, the main source of air pollution is the transport industry, and so the COVID-19 transport restrictions provided an opportunity to examine if reduction in traffic had a demonstrable impact on ambient air quality and asthmarelated admissions. Routinely collected data was used to conduct a retrospective population cohort study. The Environmental Protection Agency provided daily nitrogen dioxide (NO2) and particulate matter (PM) concentrations for Dublin, and all asthma-related admissions were collected from the Hospital In-Patient Enquiry system. The two years prior to the pandemic were compared with the period of transport restrictions (from March 2020). During the period of restrictions, there was a significant reduction in the mean number of daily asthma admissions (2.8 v 4.5 admissions p < 0.001). There was also a significant decrease in mean daily concentrations in two pollutants: NO2 (16.7 v 24.0mg/m3 p < 0.001) and PM2.5 (7.8 v 8.9mg/m3 p = 0.002). Only NO2 had a statistically significant correlation with asthma admissions (r = 0.132 p < 0.001). Transport restrictions introduced to mitigate against COVID-19 led to improvements in air quality, as seen by the reductions in pollutant concentrations. Previously described associations between pollutants and asthma, would suggest that these improvements in air quality contributed to the reduction in asthma admissions. Whereas the primary source of NO2 is transport emissions, PM is made up of particles from multiple sources, which likely explains the lack of correlation between asthma admissions and PM. Public Health need to advocate for transport policies which can improve air quality, and as a result, public health.

Key messages:
Poor air quality poses a significant health challenge requiring public health input and advocacy. Reducing vehicle traffic can improve air quality which would have a positive impact on public health.

Conclusions:
Results encourage the integration of CC topics with a focus on knowledge and professional role development into existing mandatory courses of the medical curriculum. Specifically, they also pinpoint health impacts and adaptation as greatest areas of interest for students and at health co-benefits and sustainable healthcare as areas with least prior knowledge.